Scientists Develop Sensitive Skin for Robots

Scientists at TUM are now developing an artificial skin for robots with a similar purpose as human skin: It will provide important tactile information to the robot and thus supplement its perception formed by camera eyes, infrared scanners and gripping hands. As with human skin, the way the artificial skin is touched could, for example, lead to a spontaneous retreat (when the robot hits an object) or cause the machine to use its eyes for the first time to search for the source of contact.

Such behavior is especially important for robotic helpers of people traveling in constantly changing environments. According to robot vision, this is just a regular apartment in which things often change position and people and pets move around.

The centerpiece of the new robotic shell is a 5 square centimeter hexagonal plate or circuit board. Each small circuit board contains four infrared sensors that detect anything closer than 1 centimeter. “We thus simulate light touch,” explains Philip Mittendorfer, a scientist who develops the artificial skin at the Institute of Cognitive Systems at TUM.

“This corresponds to our sense of the fine hairs on our skin being gently stroked,” Mittendorfer said. There are also six temperature sensors and an accelerometer. This allows the machine to accurately register the movement of individual limbs, for example, of its arms, and thus to learn what body parts it has just moved.

Plate for plate, the boards are placed together forming a honeycomb-like, planar structure to be worn by the robot. For the machine to have detection ability, the signals from the sensors must be processed by a central computer. This enables each sensory module to not only pass its own information, but to also serve as a data hub for different sensory elements. This happens automatically, ensuring that signals can go in alternative ways if a connection should fail.